The ItemExpire Event is fired whenever an Item expires (reaches its macimum lifespan).
It can be canceled to prevent the item from being flagged as dead.
If canceled it will add extralife to the item's lifetime.

You will need to cast the event in the function header as this class:
crafttweaker.event.ItemExpireEvent
You can, of course, also import the class before and use that name then.

Event interface extensions

Link to event-interface-extensions

PlayerDeathDrops Events implement the following interfaces and are able to call all of their methods/getters/setters as well:

ZenGetter/ZenSetter

Link to zengetterzensetter

ZenGetterZenSetterType
ZenGetter
item
ZenSetter
Type
IEntityItem
ZenGetter
extraLife
ZenSetter
extraLife
Type
int